A specialised structure − mesosome is formed by the extension of plasma membrane into the cell. Mesosomes help in cell wall formation, DNA replication and distribution to daughter cells, respiration, secretion process, to increase surface area of plasma-membrane and enzymatic content.
Bacterial cells may be motile or non-motile. Motile bacterias have flagella composed of three parts − filament, **** and basal body. Pili and fimbriae are surface structures which do not play any role in motality. These structures help the bacteria to attach with rocks and the host tissues.
